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Restoration managers inoculate microorganisms to enhance soil function and improve restoration success, but the efficacy of these inoculations in real‐world conditions is still unclear. We conducted a field experiment to test whether applying extruded seed pellets inoculated with native microbes affected soil properties related to ecosystem function in severely degraded mine soil. We found that inoculating with bacteria did not affect soil carbon, metabolic quotient (a measure of microbial stress), or basal respiration, but increased soil nitrogen by 75%, substrate‐induced respiration by 147% and reduced carbon‐to‐nitrogen ratio by 44% compared to the control. This suggests that the bacteria inoculant contained free‐living N fixers that increased the soil N content. Thus, inoculating with bacteria could supplement nitrogen fertilizers in degraded soils during soil restoration. However, we found that inoculating with a mix of bacteria and cyanobacteria did not affect any of the soil properties. This finding is counter to results in laboratory studies, suggesting that field tests are critical for understanding real‐world outcomes of microbial inoculation. Finally, we found that soil microbial composition was changed by the inoculation with a mix of bacteria and cyanobacteria. None of the treatments significantly changed the diversity of soil microbial communities. Our data suggest that microbial inoculation could improve some aspects of ecosystem function and thus provide beneficial effects that might facilitate restoration of degraded sites. [ABSTRACT FROM AUTHOR]

This article discusses the importance of integrating soil microbial communities into ecological research, conservation efforts, and ecosystem restoration. It emphasizes the need to understand the diversity and functioning of soil microbes in Australian ecosystems, particularly mycorrhizal fungi. Ongoing research projects are exploring the diversity of mycorrhizal fungi in agricultural and rainforest environments, as well as the ecological interactions that influence microbial diversity and functioning. The article also highlights the potential of soil microbes in promoting sustainable agriculture and protecting crops from climate change effects. It concludes by discussing the impacts of insect herbivory and plant pathogens on soil microbial communities and the importance of trait-based approaches in fungal ecology. A study conducted by researchers from various Australian universities and research institutions found that the richness and cover of exotic plant species were associated with increased nutrient availability and specific microbial taxa. The study also revealed that land management practices had contrasting effects on the microbiome assembly of certain plant species. Additionally, the study emphasized the important role of digging animals in soil fungal ecology and dispersal in both arid and urban ecosystems. The researchers called for further research to understand and harness the potential of soil microbial communities for ecosystem restoration and conservation in Australia. [Extracted from the article]

This study, based on vegetable production fields, combined soil quality assessed by three approaches (qualitatively by farmers, semi-quantitatively by a researcher and quantitatively by laboratory analyses) with the aim of improving the integration of the different approaches. We interviewed 79 peri-urban vegetable growers in two communities within the Sunyani Municipality, Ghana. Eight of the farmers were selected to participate in the farmer-based assessment of soil quality. Further, visual evaluation of soil quality was conducted by the researcher, followed by laboratory analyses of soil properties to corroborate the farmers' assessment of good and poor soils in their fields. Results showed that the farmers used locally-defined characteristics to describe the physical, biological and crop performance indicators of soil quality. There was, in general, limited use and understanding of soil chemical properties as indicators of soil quality. The farmers' perception on soil quality of their fields largely influenced their decision on the type of crops they cultivate, and application regimes of mineral fertilizers. Results from the visual evaluation by the researcher agreed in some respects with the farmers' assessment of soil quality of the good and poor soils in their respective farms. Laboratory analyses did not show specific trends for the content of chemical properties for neither good nor poor soils. The study highlighted that none of the approaches of soil quality assessment is necessarily superior in and of itself. We emphasized the need for integration to capitalize on the strengths of each approach, enhance mutual learning between farmers and soil scientists, build the capacity of farmers, and improve their decision on soil use for agricultural production. [ABSTRACT FROM AUTHOR]

Root morphology strongly affects the ability of crops to maximize the exploitable soil volume. This is of especial relevance for the uptake of essential but immobile nutrients such as phosphorus (P). However, the idea of the key role of root hairs in P uptake is mainly based on the fact that root hairs strongly respond in their growth, abundance, density and elongation to P deficiency in soils. Furthermore, rhizosphere properties related to nutrient uptake such as exuded carboxylate anions, exoenzymatic activity or lowered pH are frequently maximized in the zone of root hairs suggesting their key role in nutrient mobilization. However, besides such indirect hints, direct proof of the role of root hairs for P mobilization is lacking. We hypothesized that roots hairs improve P mobilization by enhancing rhizosphere acidification and exploited soil volume. Thus, we tested the capability of two varieties of maize and barley with and without root hairs for their potential to mobilize phosphorus of low availability. We applied 33P-orthophosphate (2 MBq per rhizobox) to an alkaline soil (pH 8.3). The soil was dried to ensure a strong sorption and/or precipitation of the P. Alkaline soil was chosen to specifically test for the relevance of rhizosphere acidification as key mechanism for enhanced P mobilization hypothesized to be improved by roots hairs. We used a planar optodes to visualize rhizosphere acidification along the root including the root hair zone at five different growth stages. After harvest, 33P uptake was quantified by combustion of plant and soil material and 33P determination via scintillation counting. Furthermore, we used phosphorimaging to visualize the depletion of 33P in the rhizosphere, it's uptake into roots and its allocation within the root system. N fertilization was applied hypothesizing that an increased N supply provides additional resources to boost P mobilization mechanisms.After harvest (25 days) the 33P content in the biomass was significantly higher in root hair wildtypes (WT) than in root hairless mutants. N fertilization could be proven to be a key mechanism increasing the exploitation of a larger soil volume and thus the P nutrition of both crops. Maize and barley were able to acidify the rhizosphere from 8.3 to 7.5 in average. The pH change was strongest at the young roots parts, but not directly at the root tips pointing towards the fact that accumulation of organic acids is required for reaching a significant pH decrease in this strongly buffering soil. In maize, specifically crown roots strongly decrease the rhizosphere pH. However, especially at early growth stages spatial correlation between rhizosphere acidification and P uptake as well as the root hair zone and the P depletion zone is rather low suggesting additional mechanisms contributing to the high P uptake. We conclude that root hairs are a key trait improving P mobilization and uptake from soils with low P availability. However, we observed also P depletion in far distance to the visible roots, root hairs and acidified rhizosphere suggesting additional mechanisms, such as mycorrhization, to contribute to a rather homogenous P depletion. [ABSTRACT FROM AUTHOR]